A. Field of the Invention
The embodiments of the present invention relate to a spatula, and more particularly, the embodiments of the present invention relate to an adjustable spatula for forming a smoothly arcuate concave contour in a viscous material and a smoothly arcuate convex contour in the viscous material, independently of each other, with a certainty that the contour of the viscous material is consistent, and with using only one hand.
B. Description of the Prior Art
Plaster walls have been traditionally constructed by a labor-intensive process. A common wall requires the application of three individual plaster layers, each of which must be leveled and set prior to the application of the succeeding layer. Although considerable skill is required to achieve a flat and smooth surface over a large area, the end result is a wall having an unmistakable look and feel, along with superior sound insulation properties.
The use of this skilled labor runs counter to the present trends in the commercial and home construction industry. Emphasis today is on speed, efficiency, and cost-effectiveness towards the completion and profitability of construction projects. Competitive bidding pressures have made it increasingly difficult to rely on anything other than unskilled labor when bidding a construction project.
Except for the most expensive of custom installations, gypsum wall board—also know as “dry wall”—has completely replaced plaster in the construction of walls and ceilings in modern homes and offices. Composed of a core of calcined gypsum, starch, water, and foam slurry sandwiched between special paper faces, gypsum board or dry wall retains the fire-resistant characteristics of gypsum plaster but can be installed with much less labor and by less skilled workers. In addition, the use of dry wall brings very little “water” into a job, and thereby eliminates some of the waiting required with the curing and drying of gypsum plaster.
After the core material has hardened and bonded to the paper faces, the dry wall is cut to length, heated to drive off any residual moisture, and then bundled for shipping. For the majority of commercial and home construction applications, the dry wall is cut into rectangular sheets of four feet by eight-to-twelve feet, and is one-half inch to five-eighths inch in thickness. Installation of the dry wall can occur over either steel or wood studs using self-tapping screws for metal studs and either screws or nails to fasten the dry wall to the wood support. After installation of the dry wall is complete, all of the joints between the boards and the indentations left by the nailing or screw attachments must be filled and smoothed before the surface of the dry wall is ready for final texturing or finishing.
The majority of dry wall panels used in finished wall constructions have a tapered edge to assist in forming a flush and invisible seam between adjacent panels when the joint finishing operation is completed. Finishing begins by the troweling of a layer of joint compound or plaster into the tapered edge joint formed along adjacent edges of adjoining dry wall panels. A paper or glass fiber reinforcing tape is then placed over the joint and covered with an additional layer of the joint compound. These first layers are allowed to dry, and one or two finishing coats of the joint compound are then applied and sanded. A properly finished joint forms a wall appearing to be made of a solid sheet rather than discrete panels.
Flat gypsum board also can be used to form curved surfaces. When the curves are gentle, dry wall can conform to a large radius by simply bending the panels around a curving line of support studs. For somewhat sharper curves, the paper faces of the wall board can be moistened, which decreases the stiffness of the board prior to conforming it to the shapes required upon its installation. Drying causes the dry wall to again stiffen, permitting its attachment to the underlying support structure.
In custom and semi-custom residential construction, there has been a recent trend towards providing visual features, such as rounded walls, recesses, columns, and bay window areas. In commercial buildings, the trend has been toward providing one or more “walls as art” located in the “common” areas. In each of these construction applications, there are framing irregularities, creases, and/or gaps that are created when attaching the flat dry wall materials to the supportive radius wall framing.
The majority of these features require radii that are very difficult to achieve by simply deforming the flat dry wall panels. Instead, the present practice is to cut the dry wall into multiple sections that are then pieced together to create a substantially curved surface. A smoothed and finished surface is then obtained by the application of either the joint compound or a plaster material to cover the joint irregularities. The multi-piece surface is thereby formed into a visually-continuous surface having multiple-curved surfaces expressed therein.
Achieving, however, this uniformly radiused finish has proven to be extraordinarily difficult for the dry wall laborers to achieve. In addition to requiring a higher level of skill on the part of the workman, it has proven necessary to devise specialized tools to assist the dry wall installers in obtaining the desired surface uniformity. Workmen have frequently resorted to reshaping their trowels to approximate the working edges to the desired surface radius. Other workmen have attempted to maintain the required curvature by utilizing a bent piece of cardboard.
Neither of these solutions have proven to be particularly desirable. The modified trowel must be held at a specific angle relative to the dry wall surface throughout the finishing process. This includes maintaining the angle along the entire length of a specific and curved wall feature. Also, to maintain continuity from one curvature to another, this same angle must be carefully repeated. With respect to the use of cardboard, these improvised tools are not capable of uniformly maintaining an appropriate curvature. Consequently, it has proven to be extraordinarily difficult to maintain a fixed angular position between the improvised tool and the work surface.
Thus, there exists a need for an adjustable spatula for forming a smoothly arcuate concave contour in a viscous material and a smoothly arcuate convex contour in the viscous material, independently of each other, with a certainty that the contour of the viscous material is consistent, and with using only one hand.
Numerous innovations for spatulas have been provided in the prior art, which will be described below in chronological order to show advancement in the art, and which are incorporated herein by reference thereto. Even though these innovations may be suitable for the specific individual purposes to which they address, however, they differ from the present invention in that they do not teach an adjustable spatula for forming a smoothly arcuate concave contour in a viscous material and a smoothly arcuate convex contour in the viscous material, independently of each other, with a certainty that the contour of the viscous material is consistent, and with using only one hand.
(1) U.S. Pat. No. 1,083,099 to Howg.
U.S. Pat. No. 1,083,099 issued to Howg on Dec. 30, 1913 teaches a trowel including a plate, standards fixed to the plate in spaced relation to each other and having spaced ears, a rod pivotally connected to one pair of ears, an adjusting nut swivelly connected to the other pair of ears and in threaded engagement with the rod, and a handle carried by the stem.
(2) U.S. Pat. No. 1,743,704 to Boux.
U.S. Pat. No. 1,743,704 issued to Boux on Jan. 14, 1930 teaches a plasterer's dressing plane for finishing off angles and corners of molded surfaces, which includes a smooth faced member of flexible character, and back apparatus to which the member is secured, whereby it is stayed in set contour. The back apparatus includes a train of back pieces to whose remote ends of the member are attached and which form intermediate back stays.
(3) U.S. Pat. No. 2,608,853 to Schrepper.
U.S. Pat. No. 2,608,853 issued to Schrepper on Sep. 2, 1952 in class 72 and subclass 136 teaches a corner forming tool including an elongated substantially V-shaped member including a pair of sloping side walls having inner edges joined together, a pair of elongated wall sections integrally formed with the outer edges of the side walls and inclined relative to the side walls, a substantially V-shaped deflector having a pair of sloping walls joined with the side walls of the member and having inner joined edges inclined relative to the joined inner edges of the side walls, and an adjustable connection between the elongated wall sections for adjusting the wall sections relative to each other and to the side walls.
(4) U.S. Pat. No. 2,968,057 to Pratt.
U.S. Pat. No. 2,968,057 issued to Pratt on Jan. 17, 1961 in class 15 and subclass 236 teaches a contour knife including a flat and flexible member having a first straight end, a second smaller end, two tapering sides connecting the ends, and apparatus to curve the member including a clamp connected to the two sides. The clamp includes a hollow and tubular member notched on one end to fit the edges of the flexible member, and a threaded bolt passing through the tubular member. The smaller end is curved and adapted to fit in the palm of the hand. A molded lip is on the smaller end to facilitate holding in the hand.
(5) U.S. Pat. No. 4,130,269 to Schreyer.
U.S. Pat. No. 4,130,269 issued to Schreyer on Dec. 19, 1978 in class 254 and subclass 67 teaches a ratchet-type telescopic load binder having axially and oppositely moveable first and second threaded screw members of different diameters. The larger diameter member includes an axial and cylindrical void into which the smaller screw member is permitted to move. Greater reach is achieved by providing the smaller member with a screw thread pitch and a thread length being greater than those of the larger member. The cylindrical void of the larger member extends past its operative thread length to accommodate increased penetration of the smaller member.
(6) U.S. Pat. No. 4,496,500 to Haber.
U.S. Pat. No. 4,496,500 issued to Haber on Jan. 29, 1985 in class 264 and subclass 36 teaches a method for shaping a motor vehicle panel. Body filler material is applied to a damaged area of a panel and allowed to harden partially. Using back and forth strokes, a saw-toothed blade is used to shape the partially hardened material to the desired contour. The blade should be flexible to allow the user to bend it to the shape of the panel.
(7) U.S. Pat. No. 4,631,019 to House.
U.S. Pat. No. 4,631,019 issued to House on Dec. 23, 1986 in class 425 and subclass 458 teaches a flat, quadrilateral, and resilient spreader member, symmetrical about its longitudinal axis, has mutually convergent longitudinal edges, and has handle members removably attachable along its longitudinal edges for bending the spreader member while being used in the application and shaping of moldable material to a work-piece.
(8) U.S. Pat. No. 4,669,970 to Perry.
U.S. Pat. No. 4,669,970 issued to Perry on Jun. 2, 1987 in class 425 and subclass 458 teaches an adjustable hand-tool for finishing corners, edges, and the like with cementious material to effect a uniformly rounded configuration to the corner. The hand tool includes a backing plate having a forward working edge characterized by an indented central portion and forwardly extending legs forming a first obtuse angle. Overlaying the backing plate is a pliable sheet having a forward working edge characterized by an indented central portion and forwardly extending legs forming a second obtuse angle that is larger than the first obtuse angle, so that the working edge of the pliable sheet extends beyond the working edge of the backing plate. The backing plate is preferably manually bendable to suit an individual craftsman and to obtain a working region having cooperating curvatures at the working edge of the backing plate, at the working edge of the pliable sheet, and as caused by the bend.
(9) U.S. Pat. No. 4,757,572 to Yon.
U.S. Pat. No. 4,757,572 issued to Yon on Jul. 19, 1988 in class 15 and subclass 235.7 teaches a hand finishing tool for dry wall board installation, which includes three operative components. A main body including a planar sheet material is formed into two substantially flat sides extending radially from the common line to define a dihedral configuration, a manual tool gripping apparatus pinned at its stem end to the inner surface of the main body, and a tool angle biasing apparatus adapted upon digital manipulation to outwardly bias the flat sides to temporarily enlarge during tool use the angle that the sides normally define.
(10) U.S. Pat. No. 5,192,558 to Sparrow et al.
U.S. Pat. No. 5,192,558 issued to Sparrow et al. on Mar. 9, 1993 in class 425 and subclass 87 teaches a plaster's tool having a flexible blade with a handle coupled to a member for dynamically folding the blade, so that the tool may be manipulated and the blade dynamically folded by a person holding the handle to assume the correct angular configuration for laying a plaster bead along the outside corner formed by the juncture of two surfaces meeting at an angle of 180° or greater. The blade readily assumes a flat and planar configuration providing easier loading of plaster onto the tool and the transfer of the plaster on the flat blade to the work surface.
(11) U.S. Pat. No. 5,467,497 to Greene et al.
U.S. Pat. No. 5,467,497 issued to Greene et al. on Nov. 21, 1995 in class 15 and subclass 235.8 teaches an adjustable drywall corner tool, including a pair of work-engaging blades normally disposed substantially at a 90° angle to one another. A hinge extends between mating edges of the blades. A structure is for changing the angle between the two blades, so that the blades will fit in an inside corner of more or less than the 90° angle. A handle extends from the angle changing structure, so that a person can grip the handle to apply taping to the corner.
(12) U.S. Pat. No. 5,544,384 to Forselius et al.
U.S. Pat. No. 5,544,384 issued to Forselius et al. on Aug. 13, 1996 in class 15 and subclass 235.7 teaches a wall corner finishing tool including a pair of plastic blades connected by a living hinge. The proximal ends of a pair of arcuate arms are hingeably connected to the back sides of the blades. The arms are curved toward each other so as to overlap at their intersection. The arms include longitudinal openings extending therethrough. A handle is attached to the intersection of the arms by a screw extended through the openings and into one end of the handle. When the screw is loosened, the arms move toward or away from each other to adjust the angle between the blades. When the blades are positioned at a desired angle, the screw is tightened to fix them in position. The blades can be adjusted for finishing wall corners of a great variety of angles.
(13) U.S. Pat. No. 5,611,102 to Lesinsky et al.
U.S. Pat. No. 5,611,102 issued to Lesinsky et al. on Mar. 18, 1997 in class 15 and subclass 235.5 teaches a tool for applying a viscous material to a curved surface, which includes a thin, flexible, and planar blade having first and second side edges, and first and second elongate handles depending from the blade. The first and second handles are attached to the blade near the first and second side edges, respectively, and are configured to be manually grasped by a user of the tool.
(14) U.S. Pat. No. 5,774,924 to Beckham et al.
U.S. Pat. No. 5,774,924 issued to Beckham et al. on Jul. 7, 1998 in class and subclass 235.7 teaches a cornering tool used for application of drywall or plaster or similar construction coating materials. The tool is adjustable over a wide range of corner angles. In addition, the adjustability allows for use in plastering as well as drywall application where the angle is offset to effect screeding of excess coating material. The tool includes a thinned hinge section with increased flexibility allowing for angular adjustment of the blades without bending the blades out of plane. The tool is preferably formed of plastic.
(15) U.S. Pat. No. 5,792,489 to Liberman.
U.S. Pat. No. 5,792,489 issued to Liberman on Aug. 11, 1998 in class 425 and subclass 458 teaches a tool for spreading bonding compound simultaneously on two planar surfaces intersecting along a common border. The tool includes a wedge-shaped applicator having first and second applicator blades meeting at a substantially right angle along a linear vertex. The blades extend away from the vertex and terminate at opposite lateral sides. The wedge-shaped applicator has an interior portion defined within the substantially right angle. Also included is a handle for gripping the tool and connected to proximal ends of the blades. The blades have forward edges disposed opposite the proximal ends, with the forward edges having outside surfaces to facilitate application of the bonding compound. A flexible applicator strip is disposed along a portion of the forward edges. The first and second applicator blades each have a bent corner causing the outside surfaces of the forward edges to bend forward in a direction away from the interior portion of the applicator blade. The bent corner causes the flexible applicator strip to bend therewith forming a bent flexible contour, so that the flexible contour assumes a substantially linear shape when forced into contact with the planar surfaces and advanced along the planar surfaces by the handle.
(16) U.S. Pat. No. 6,003,192 to Ciminise et al.
U.S. Pat. No. 6,003,192 issued to Ciminise et al. on Dec. 21, 1999 in class 15 and subclass 235.5 teaches, as shown in FIGS. 1 and 2, which are, respectively, a diagrammatic perspective view of a typical prior art tool being used to form an arcuate surface in a viscous material, and an enlarged diagrammatic front elevational view of the area generally enclosed by the dotted curve identified by ARROW 2 in FIG. 1 of the typical prior art tool, a typical prior art hand tool 20 includes a flexible blade 22 having a working edge 24 for use with a cementitious material 26 for permitting forming and finishing of a column 28 and other curved surfaces of relatively large radii. A pair of gripping surfaces 30 are formed in the flexible blade 22, which include handles 32 to which handgrips 34 are attached. To enhance ability of a user 36 to control curvature of the working edge 24 of the flexible blade 22, the handgrips 34 are attached to the handles 32 in a manner so that a portion of each handgrip 34 overlies, and is supported by, an outer lateral portion 38 of an associated handle 32. This arrangement permits the user 36 to apply force through the handgrips 34 directly to an outer periphery 40 of the flexible blade 22. The typical prior art hand tool 20 requires a need for the user 36 to have to manually bend the flexible blade 22 and hold it bent throughout its operation by the two hands of the user 36, thereby eliminating a certainty that the contour of the viscous material is consistent throughout the operation.
It is apparent that numerous innovations for spatulas have been provided in the prior art that are adapted to be used. Furthermore, even though these innovations may be suitable for the specific individual purposes to which they address, however, they would not be suitable for the purposes of the embodiments of the present invention as heretofore described, namely, an adjustable spatula for forming a smoothly arcuate concave contour in a viscous material and a smoothly arcuate convex contour in the viscous material, independently of each other, with a certainty that the contour of the viscous material is consistent, and with using only one hand.